This invention relates to a latching and tensioning device for band clamps, steel straps, v-band couplings and the like. More specifically, this invention relates to such a device which can provide adjustable tensioning without the requirement of utilizing any tools.
Items such as band clamps which can be used, for example, to couple a hose to a fitting, steel straps which can be used, for example, to bind loose elements of a load together, and v-band couplings which can be used, for example, to couple the circumferential flanges of axially adjacent pipes or the like, need to be provided with some type of tensioning device. These clamps and the like are continuous items but for a gap which is formed between opposed ends, the size of which controls the amount of tension being placed on the clamp. Thus, the gap is closed by some form of tensioning device.
Most simply, this tensioning device can be an overcenter link latch where a link is provided at one of the ends and is captured by a rotating leverage handle carried by the other end. In this way, the two opposed ends are connected to each other. However, these devices suffer in that they only provide one degree of tension, that is, the amount of tension provided by the device cannot be adjusted. As a result, these types of clamps can only be utilized for applications where a single-sized item is consistently to be clamped with the same tension.
In response to this limitation, adjustable tensioning devices have been developed whereby the user may adjust the gap between clamp ends until the clamp is fully tensioned. Central to the design of these devices is a threaded fastener which can be turned by means of a tool, such as a wrench, until the desired tension is obtained.
In the past, these adjustable devices have taken on several forms. In most all of these forms, there is a threaded bolt with a crosspiece at the end thereof thereby forming what is known as a t-bolt. In the most basic of these types of devices, one of the ends of the clamp is provided with a trunnion through which the bolt passes. The xe2x80x9ctxe2x80x9d end of the bolt is captured by the other end of the clamp. The trunnion provides a bearing surface for a nut as it is tightened on the threaded bolt to draw the ends together until the desired tension is reached. When the tension on the clamp is to be removed, the nut must again be turned on the shaft.
In a similar device, the crosspiece is captured by an open hook carried by one end of the clamp. The device is tensioned in the same way, as by turning a nut against a trunnion. In another instance, a yoke can be hinged to a rotating leverage handle which serves as an overcenter handle latch. In this device, once the proper tension is placed on the device by turning the nut on the shaft, the opening of the handle can loosen the clamp without having to change the tension setting by rotating the nut on the shaft.
In all instances, in order to provide an adjustable tensioning device, a separate tool must be used to create the tensioning which can, in many instances, represent an inconvenience to the user.
It is therefore an object of the present invention to provide a latching device for a clamp or the like which can be utilized to adjust the tension on the clamp.
It is another object of the present invention to provide a latching device, as above, which can be operated without the need for a separate tool.
It is an additional object of the present invention to provide a latching device, as above, which includes an overcenter closure and a ratchet which can be advanced while at the same time maintaining the established tension.
It is a further object of the present invention to provide a latching device, as above, which is easy to operate and convenient to use.
These and other objects of the present invention, as well as the advantages thereof over existing prior art forms, which will become apparent from the description to follow, are accomplished by the improvements hereinafter described and claimed.
In general, a clamping apparatus made in accordance with the present invention includes a device having a first end and a second end. A ratchet link having teeth is carried by the first end. A pawl is pivotally carried by the second end and is adapted to engage one of the teeth. A handle is also pivotally carried by the second end, and a yoke is pivotally carried by the handle. The yoke is adapted to engage a different tooth such that upon pivoting of the handle, the yoke moves the link so that the pawl engages a different tooth.
In accordance with another aspect of the present invention, the clamping apparatus includes a device having a first end and a second end with a ratchet being pivotally mounted relative to the first end on a first axis. A handle is pivotally mounted relative to the second end on a second axis and a pawl is pivotally mounted relative to the second end and is adapted to engage the ratchet. A yoke is pivotally carried by the handle on a third axis and is adapted to engage the ratchet to move the ratchet upon rotation of the handle. The yoke is clamped in place when the third axis is below a line extending between the first axis and the second axis.